The drop decides everything else
A tablecloth is the table plus twice the drop in each direction. That is the whole geometry. What varies is the drop, and it is a judgement about use rather than a standard:
| Drop | Where it suits | What it does |
|---|---|---|
| 6 to 8" | Casual and bistro, everyday family table | Clears laps entirely, easy to wash, reads informal |
| 10 to 12" | Buffets, side tables, a dressed look without formality | Covers the table edge and a little more |
| 15" | Seated dining, the common formal figure | Falls to about chair-seat height, drapes without being sat on |
| To the floor | Event and display tables, cocktail rounds | Hides the table legs and anything stored under it |
Fifteen inches is quoted so often that people treat it as a rule. It is a convention that happens to land near the seat of a standard dining chair, which is why it works. On a table with a deep apron or an unusual height it can land badly, and the way to check is with a tape held at the edge rather than with arithmetic.
Where the seams go, and the centre seam problem
Table linen goods are commonly 54 inches wide, of which about 53 is usable after the selvages. Any cloth finishing wider than that needs a seam. The naive way to do it is to sew two full widths together, and the result is a seam running exactly down the centre of the table, under the middle of every place setting, where it collects wine and shows at every meal.
The workroom answer is to split the second width lengthwise and sew a half to each side of a full centre panel. The yardage is identical, you sew two seams instead of one, and both of them fall out near the table edge or over the drop, where they are barely visible. For three widths the same logic applies with a full centre and two flanking pieces. This is the single most useful thing to know about making table linen and it costs nothing to apply.
The other route is to sidestep the seam entirely with wide goods. Sheeting is sold up to about 118 inches wide, which covers a floor-length cloth for most round tables in one piece. It is a different hand from decorator linen and worth seeing before ordering, but on a large round table it removes a genuinely awkward construction problem.
Round cloths, and why the hem is the hard part
A round cloth starts as a square of the finished diameter plus hem allowance, seamed to width first if necessary, then folded in quarters and marked with a string and a pencil from the centre. Cut once, through all layers, and check the fold lines are square before you commit.
The hem is where round cloths defeat people. A curved edge cannot take a doubled straight hem, because the outer edge of the turn-under is longer than the line it has to lie against. Your options are a narrow rolled hem, which eases the small excess away; a bias binding applied to the edge, which handles the curve properly and is what the bias binding calculator sizes for you; or a shaped facing cut to the same curve. All three work. A one inch doubled hem on a 120 inch circle does not, and no amount of pressing will make it.
Napkins and skirting
Napkins are the easy part and the reason to buy the fabric all at once: they cut from the same goods in rows across the width, so a set of eight 18 inch napkins takes about two rows and around a yard and a half depending on the width. Common finished sizes run roughly 16 to 18 inches for lunch and 20 to 22 for dinner, again as convention rather than requirement.
Table skirting is a different construction: a gathered or pleated band the height of the table, attached to the top edge and running round the perimeter. The length of cloth in it is the perimeter times the fullness ratio, so a 2x skirt on a 60 inch round table needs about 377 inches of gathered strip, which is eight strips off 54 inch goods. Fullness is a look: 1.5x is a light gather, 2x is standard, 3x reads as pleated. If one side is against a wall, you can drop that side and save the fabric, which is what the checkbox does.
If you are working out the finished sizes of the pieces first and want the layout checked against another fabric width, the fabric yardage calculator will lay a cut list out for you, and the seam allowance and cut size calculator converts finished dimensions to cut dimensions for anything not covered here. For fabric on windows in the same room, the curtain size calculator handles the panel sizing and fullness.
Questions people ask
What size tablecloth do I need for a 60 inch round table?
Add twice the drop to the diameter. A 15 inch drop gives a 90 inch round cloth, which is the common seated dining answer. A floor length cloth on a 30 inch high table gives 120 inches. An 8 inch bistro drop gives 76. None of those fit across 54 inch goods, so all of them need either seaming or wide sheeting, which is why the seam plan is part of the calculation rather than an afterthought.
How long should a tablecloth hang over the edge?
For seated dining, 15 inches is the figure most people use, because it falls to roughly chair-seat height and drapes without ending up in anyone lap. For casual and everyday use 6 to 8 inches is easier to live with and much easier to launder. For display and event tables, to the floor. All of these are conventions rather than rules, and the honest test is to hold a tape at the table edge and look at where each length lands with the chairs pushed in.
How do I avoid a seam down the middle of the table?
Do not join two full widths. Cut one full width for the centre and split a second width lengthwise into two halves, sewing one to each side. The total fabric is the same, there are two seams instead of one, and they land out near the table edge instead of down the centre of the place settings. This is standard workroom practice for both cloths and bed coverings, and it is worth the extra seam every time.
How much should I add for shrinkage on table linen?
More than you would for something that gets washed rarely, because table linen gets washed hot and often. Cotton and linen both move on the first wash, and linen keeps moving a little for several washes. The default here is 5 percent, applied to both the length you buy and the usable width, which is a working figure and not a measurement of your fabric. The reliable approach is to prewash the whole piece the way you intend to launder the finished cloth, then cut. That way whatever is going to happen has already happened.
How much fabric for a table skirt?
Perimeter times the fullness ratio gives the gathered length, then divide by the usable fabric width to get the number of strips, each cut to the table height plus hems. A 6 foot rectangular banquet table has a 204 inch perimeter; at 2x fullness that is 408 inches of gathered strip, about eight strips from 54 inch goods, each around 32 inches tall for a 30 inch table. That comes to roughly seven yards. Drop the back side if the table stands against a wall and it falls by about a quarter.